Bug 95056 – Web Inspector: provide a way for finding setTimeout/XHR callbacks referenced from native code

• Status: RESOLVED
• Resolution: INVALID
• Component: Web Inspector (Deprecated)

[Yury Semikhatsky]

Now we have global handles referencing such callbacks and it is hard to say whether they are references created by setTimeout/Interval/XHR or some browser internal things. We need a way to determine if a global handle is one of such references.

[Yury Semikhatsky]

Resolving this issue would require creating heap graph entries for each setTimeout callback that would reference the function and the arguments passed to the setTimeout call. After discussing this problem with Ilya it seems that it cannot be efficiently solved using existing mechanisms for reporting additional data about global handles. There are two way to provide some data on global handles to v8 heap profiler:
1) v8::Persisitent<T>::SetWrapperClassId that allows to classify given handle using uint16_t and then retrieve RetainedObjectInfo object for that class using a callback set via v8::HeapProfiler::DefineWrapperClass
2) Report RetainedObjectInfo by means of v8::V8::AddObjectGroup

Instead of extending this quite tricky API we'd rather move part of the logic that deals with DOM groups and related stuff from v8 to WebCore and have v8 only collect information about JS heap.